Polyhedrons having depressible vertices and internal means for restoring shape

ABSTRACT

A SIXTY-SIDED HOLOW POLYHEDRON STRUCTURE IS DESCRIBED FOR USE AS A TOY. THE POLYHEDRON IS PROVIDED WITH SUBSTANTIALLY STATIONARY VERTEXES AND RADIALLY MOVABLE VERTEXES. INWARDLY-DEPRESSED VERTEXES MAY BE POPPED OUTWARDLY WITH THE USE OF A BALL RETAINED WITHIN THE STRUCTURE. THE OUTWARD MOVEMENT MAY BE ACCOMPANIED BY A POPPING SOUND.

p 20, 1971 w. H. ADAMS 3,605,324

romasnnous mwme DEPRESSIBLE VERTICES AND INTERNAL MEANS FOR ass-mama srmrn Filed March 7, 1968 /a n I VA VAV United States Patent Ofilce 3,605,324 Patented Sept. 20, 1971 U.S. CI. 46-42 4 Claims ABSTRACT OF THE DISCLOSURE A sixty-sided hollow polyhedron structure is described for use as a toy. The polyhedron is provided with substantially stationary vertexes and radially movable vertexes. Inwardly-depressed vertexes may be popped outwardly with the use of a ball retained within the structure. The outward movement may be accompanied by a popping sound.

Geometric toys have always been an invaluable instruction tool for children at play. For instance, common building blocks are provided with special interrelationships that teach in a most elementary way the geometric series 1, 2, 4, '8, 16, etc.

Other educational geometric structures have been employed as, for instance, illustrated by the patents to Berry 2,839,841, and Hedberg 3,359,657. In the former patent various polyhedrons are illustrated to simulate molecular structures. Hedberg illustrates how a polyhedron structure may be formed from a flat sheet having scored lines along which folds are made to form the structure.

"However, none of these prior 'art structures have the unique characteristic of acting like a suitable toy, i.e. with the capability of moving surfaces. The polyhedrons constructed by Berry do not exhibit in three dimensional form the characteristic of a movable surface. Their vertexes contain angles which are too sharp to permit depression without distortion or destruction. Furthermore, even when one succeeds in constructing a twenty sided regular polyhedron of such a mate-rial that a vertex can be depressed, its return to normal form is difficult to accomplish unless special arrangements are provided.

I have found that the depressibility of a vertex is of utility with a closed polyhedron as a toy to a child whose imagination and interest are greatly stimulated thereby.

SUMMARY OF INVENTION It is therefore an object of this invention to provide a closed hollow polyhedron structure having stationary and radially movable vertices.

It is another object of this invention to provide a closed hollow polyhedron structure having stationary and movable vertices and being provided internally with means for restoring a depressed vertex.

It is still further an object of this invention to provide a closed hollow polyhedron structure from precut sheet materials.

DESCRIPTION These objects are accomplished as hereinafter described in relation with the figures wherein FIG. 1 illustrates a preferred embodiment of a hollow 60 sided polyhedron structure enclosing a ball.

FIG. 2 illustrates the construction of the polyhedron of FIG. 1.

FIG. 3 illustrates the precut fiat sheet and form for one half of a polyhedron.

FIG. 4A and FIG. 4B illustrate the depressibility of a vertex of the polyhedron.

In FIG. 1 a closed 60 sided polyhedron is shown wherein each side comprises an equilateral triangle.

The triangles 12 are all joined along their edges 20 by a tab mechanism described in relation to FIGS. 2 and 3. The polyhedron structure 10 is hollow and encloses an object 16, such as a lightweight ball. The polyhedron 10 comprises various vertexes.

A first vertex 11 is formed by five equilateral triangles 12 which together constitute a pentagonal segment. A second vertex 14 is formed by six equilateral triangles 12 which together constitute a hexagonal segment. There are in all twelve pentagonal segments or ten hexagonal segments.

The pentagonal and hexagonal segments are interlocked, but they are unlike in another important aspect. Thus the pentagonal vertices protrude further out than the hexagonal vertices, and as a result the solid angle formed by the pentagonal segments is more acute or smaller than the solid hexagonal 'vertex angle. I have discovered the hexagonal angle to be capable of radially inward depression without destroying the structure. The pentagonal vertex cannot :be so depressed without damaging the polygonal structure. The ball inside the polyhedron 10 may then be used to return the vertex i14 to its outward position by appropriately shaking the structure 10.

In FIG. 3 a precut fiat sheet 27 for one half of a polyhedron structure of the type in FIG. 1 is shown. The sheet material may be made of thin cardboard which is stiff and is provided with scored or bendable edges 20 which form the edges of the triangles 12. In addition tabs 28 are provided to permit joining of the edges to form an enclosed structure 10. The flat sheet 27 comprises six heagonal sections each having six equilateral triangles. One of these triangles comprises a plurality of tabs 28 to form a half, or thirty sided polyhedron. The hexagonal sections are transformed into pentagonal segments with vertices 11 when the triangles are joined. Two sheets of the type shown in FIG. 3 are joined to form an enclosed sixtysided polyhedron structure 10.

In FIG. 2 the partially constructed polyhedron structure 10 is shown. As can be seen the tabs with like numbered dots are joined. Thus tabs 26 are glued together as well as tabs 22 and tabs 24. The tabs shown may be left to project inwardly as shown in FIG. 4 but preferably the edges after joining are further glued to the underside of one of the adjoining triangles to provide both edge reinforcement and structural integrity. The latter step may be conveniently accomplished after application of glue by a thin tweezer which is applied through any one of the vertex holes 14 and can reach all of the triangles and tabs.

After construction the vertex 14 can be depressed by the finger as shown in FIGS. 4A and 4B. The vertex 14 moves inwardly the same distance it ordinarily protrudes above the line formed between vertexes 18.

The ball 16 inside the sixty sided polyhedron structure 10 may be used to pop the hexgonal vertices outwardly by shaking the structure. Even with the most rudimentary aim one may restore the depressed vertex, while the accompanying popping sound produced thereby is an additional advantageous characteristic.

The toy may be rolled down an inclined surface in which case it rolls in quite an amusing fashion due to the ball inside and when tossed floats eccentrically. The triangles 12 further may be provided with different color schemes which would enhance its value as a plaything: by depressing various vertices different geometric shapes can be formed, such "as three', four-, and five-pointed stars; and because of the various colors employed, these shapes are quite distinct in appearance.

Alternate polyhedron structures have been considered such as the sided regular polyhedron but the triangles of such structures then tend to become too small and the depression of a vertex may then also affect many more segments and the popping sound associated with the sixty sided polyhedron is lost. Similarly the twenty sided polyhedron does not have' sufiiciently large solid vertex angles to permit depression of one in the fashion of my invention.

Having thus described my invention in a preferred embodiment of a polyhedron others can be constructed with depressible vertices without escaping the full scope of my invention as described by the following claims.

I claim:

1. A toy comprising a hollow closed polyhedron structure formed of a thin sheet material divided into a plurality of geometric surface elements joined to one another along bendable edges, with selected groups of elements arranged to meet in common polyhedral vertices which are radially inwardly depressible to a stable position and means located for free movement within the hollow of the polyhedron structure for moving depressed vertices outwardly to restore the polyhedron structure to a normally desired shape.

2. A toy as recited in claim '1 wherein said means comprises a lightweight ball.

3. A toy as claimed in claim 1 wherein each of said References Cited UNITED STATES PATENTS 1,292,188 1/1917 Wheeler 3572X 1,997,022 4/1935 Stalker 35-72X 2,424,601 7/1947 Crouch 229-8 FOREIGN PATENTS 114,899 l1/ 1929 Austria 273146 505,435 12/1954 Italy 273-58.8

F. BARRY SHAY, Primary Examiner US. Cl. X.R. 

